2005 4.2TDI GU No power to ignition control fuse.

[Halvorsen]

Hi All,

Seeking advice, currently have problem starting vehicle.
Engine cranks but wont fire up.
Noticed immobliser light on constant when ignition is on.
Have found no voltage either side at ignition control fuse panel inside vehicle.
Does any one know where this fuse is supplied from??

Any advise would appreciated, wiring schematic ideal

[nissannewby]

The little black box on the back of the injector pump has probably shit itself.

[Yendor]

What fuse doesn't have power?........fuse 25?

Are you checking with the ignition switched on?

[Halvorsen]

Hey Yendor,
Fuse # 26 from memory, have checked with ignition ON, all other fuses in panel have power.
Trying to understand the magic of the immobiliser controls.
As i understand, chip in ignition key talks to reciever in steering wheel, this allows solenoid on IP open, engine starts, controlled via immobiliser computer?
I am not sure if the ignition control fuse feeds reciever in sterring wheel or immobiliser computer, or power to IP solenoid.
Presuming solenoid if OK as i have no ignition control power.

[Yendor]

Fuse 26 (7.5amp) is a start signal fuse.....it only has power when you turn the ignition key to start.

Fuse 25 is the main ignition fuse for the NATS. Make sure this fuse has power both sides when ignition is turned on.

Normally a NATS problem with the TD42 is a faulty control module mounted on the back of the injector pump.

There is a chip in the original key/s that is read by a sensor mounted around the ignition switch.

When the sensor around the ignition switch receives the correct signal it sends a "ok to start signal" to the module mounted on the back of the injector pump. This module then switches power to the fuel control solenoid in the injector pump and then the vehicle can start.

Some people with TD42s when they have a problem with NATS choose to remove the control module from the back of the injector pump and bypass the NATS altogether.

[Halvorsen]

Thanks Yendor,

I will recheck the fuses and cross my fingers!

Sounds like fun and games to bypass fuel control soleniod, pretty tight for room down there if i'm looking at the right place.

Not sure i would attempt.

[Halvorsen]

Hi Yendor,
thanks for the schematic
rechecked fuses and all are fine (bugger)
checked injector pump for NATS solenoid, believe i have found it and it has 12V at electrical plug.
The third cable at the plug i assume is the signal from the NATS IMMU? This will switch the CSOLU on when key is verified?

My next question,
how do i check that the ignition key is being read by the NATS?
how can you check that the NATS is sending the signal to the CSOLU? What voltage is the signal, can i be measured, presume not 12v.
Where is the NATS IMMU, saw a black box behind drivers kick panel, seems to have same number of wires as the schematic on its plug.

[Yendor]

There should be 3 wires going to the black box on the injector pump.

Brown wire has 12 volts when ignition is turned on
Black is earth
Light Green receives the.... it's ok to start signal.

You are unable to tell if the key chip has been read correctly or if it is sending an ok to start signal. As far as I can tell, even Nissan can't tell this.

The signal is not a set voltage it is either a rolling type code or data communication sent between the two modules.

When you turn the ignition on and go to start the vehicle, the red security light should turn off. Normally when the NATS plays up on the TD42 it is a CSOLU fault.

If you want to have the NATS repaired you will need to take the vehicle to a Nissan dealer, regardless of what component is faulty, as it need to programmed to the vehicle.

The box behind the drivers side kick panel will be your glow plug controller, the NATS unit is up behind the glove box.

Did you purchase this vehicle not running?

[Halvorsen]

Looks like a trip to Mr Nissan,

Thanks for your help Yendor

Have had vehicle since new, I will post Nissan's diagnosis

[NP99]

Mat, is this the same problem you and Steve worked on with Steve's truck?